Lung Cancer accounts for 13% of all Cancer cases, and 18% of all Cancer-related deaths. It is the most common Cancer diagnosed in males, and the 4th-most common in females. Incidence varies in different ethnicities around the world (African Americans had the highest incidence rates of Lung Cancer - 7%, while Swedes had the lowest - 2%).
What are the top risk factors that can cause Lung Cancer?
Cigarette smoking is the biggest risk factor driving Lung Cancer around the world. Globally, it is responsible for nearly 85 to 90% of all cases of Lung Cancer.
A smoker is at 10X-30X more risk of developing Lung Cancer, as compared to a non-smoker. Almost all forms of smoking can cause Lung Cancer, even second hand smoke.
Other prominent risk factors include:
- Asbestos exposure
- Arsenic exposure
- Genetic predispostion (Family history of Cancer)
- Exposure to radiation
- Prior radiation therapy for Breast Cancer and Lymphomas
What are the most common symptoms of Lung Cancer?
It is important to understand that the signs and symptoms of Lung Cancer can arise from both local effects of tha tumor, or from effects seen due to a distant spread (when the Cancer has metastasized to distant organs).
Local effect symptoms of Lung Cancer include:
- Nagging or persistent cough
- Blood in sputum
- Persistent chest pain
- Shortness of breath
- Change in voice
- Pleural involvement
- Superior Vena Cava Syndrome 
- Pancoast Syndrome 
The most common organs involved in the distant metastasis of Lung Cancer, include the liver, bones, the brain, and adrenal glands.
The most common Paraneoplastic syndromes for Lung Cancer include hypercalcemia, SIADH, etc.